Expendable launchers (e.g., multistage rockets) are typically used to place artificial satellites into low earth orbit (LEO). Many expendable launchers are derivatives of 1950s-era ballistic missiles. Back then, cost was not a major consideration in their design and operation. Now cost is a concern, especially with the rise of commercial space transportation.
The constantly shrinking size of electronics is making possible ever smaller satellites. New uses of small satellites weighing as little as ten pounds are envisioned.
However, the cost of launching small satellites is very high, typically at least three times higher than for large satellites on a per pound basis. Moreover, launch sites in the United States are few. Launches from the east coast of the United States are performed at the Kennedy Space Center at Cape Canaveral, Fla., and launches from the west coast are performed at Vandenberg Air Force Base in California. If a launch vehicle is tied to one of these sites, scheduling delays can result due to availability and weather. In addition, launch vehicles are constrained to tight launch windows and a narrow selection of orbits. These factors increase the cost of launch operations and preclude flexibility in launch windows and attainable orbits.
It would be desirable to reduce the cost of launching small payloads. It would also be desirable to increase the flexibility in launch windows.